Vat dye and process of making.



UNITED STATES ATENT @l ldltlli;

ALBRECHT SCHMIDT AND ERNST BRYK. oi'HocHsnoitTHE-rmm, GERMANY, AS- SIGNORS '10 FARBWEBKIE VORM. MEISTER LUCIUS & sat'imno, on HGCHST-ON-THE- MAIN, GERMANY. A CORPORATION or GERMANY.

VAT DYE AND PROCESS F MAKING.

outwit.

N0 Drawing.

To all whom it may concern:

Be it known that we, i'innnnon'r SGHMIDT, Ph. D., and ERNST Burn, Ph. 1),, citizens of the Empires of Germany and Austriallungary, respectively, residing at Hochston-the-lllain, Germany, have invented certain new and useful Improvements in the Manufacture of Vat Dyestuffs, of which the following is a specification.

lVe have found that by reducing orthoortho-dinitrothioindigo and its substitution roducts, such as ortho-ortho=dinit1'o-parapara-dichlorothioindigoes, to the corre sponding ortho ortho diaminothioindigocs, "valuable vat-dyestuffs are obtained which dye cotton and wool in the hydro-sulfite vat fast bluish-gray to blackish-blue tints. Orthoortho dinitrothioindigo and ortlio ortho dinitro-pa apara-dichlorothioindigo can he obtained from the ortho-nitrophenyland ortho nitro para chlorophenylthioglyeollic acid respectively by treating them with chlorosulfonic acid. The general formula of these products is:

Example I: The ortho-ortho-dinitrothioindigo to be used as parent-1naterial for the orthoortho-diaminothioindigo is obtained in the form of an orange brown powder by gradually introducing for instance 30 of ortho-nitro )honylthioglycollic acid into lit) of chlorosulfonic acid at about while st irring, by continuing to stir for some time until a small quantity only of the parvnt-niaterial traceable, pouring the mixture on ice, filtering, boiling first with a diluted solution of carbonate of soda and. then with water, and tin-ally drying; the mass. n. of this t)l'lllU-OllllU-tlllllll'O- thioindi'tfoor preferably a corrcspoiuling quantity of a I)tl lt3 of a certain degree of dryness are heated up to about. 80 with a. solution of 25 of crystallized sodium sullitl in water, with or without addition of sulfur, while stirring for some hours. The paste thus obtained is filtered and well washed with hot water. The dry product forms, a black powder which dissolves in comrentralml sulfuric acid with an azureblue color; on treatment with hydrosultite it yields a rat which dyes wool and cotton steel-blue to blackish-bide tints. By treat- Speeification of Letters Patent.

Patent ed lllay 31, 1910*.

Application filed August 14, 1909. Serial No. 512,811.

ing this dyestulf with halogen, still faster tints can be obtained.

Example II: If in Example I, instead of 250 of ortlio-ortho-dinitrothioindigo, there are used gr. of ortho-or-tho-dinitropara-para-dichlor )thioindigo, which may be obtained in the form of a dark reddishbrown powder from the ortho-i'iitro-paraclilorophenylthioglyeollic acid in a similar manner as the ortho-ortho-dinitrothioindigo, the Oll'll() OllillO-(llflll'llllO-Pfl a-para-diehlorothioindigo is produced, in the form of a blackish-blue powder, soluble in sulfuric acid-monohydrate with a steel-blue color; on treatment with hydrosulfite it yields a \at which dyes wool and cotton steel-blue to blackish-blue tints. The formula of this product is:

On reduction, the or'tho-ortho-dinitro-parapara-diln'omothioindigo obtainable from the ortho nitro pa ra bromophenylthioglycollic acid shows similar properties.

Instead of efl'ecting the reduction by means of sodium sullid, other known reducing agents may be employed for this purpose.

The new products are black to blackishhlue powders, insoluble in water, alcohol and diluted acids, and ditlicultly soluble in hot nitrobenzene with a violet-brown to Violet. color.

Having now particularly described our invention what we claim is:

l. The process of manu'tacturingvat-dyest u (is, which consists in reducing ortho-orthodinitrothioindigo and the ortho-ortho-dinitro-paraara-dihalogentlnoindigoes, substantially as above described.

As new products, the o1'thoorth0-di aminothioindigoes of the geneal formula:

wherein X represents hydrogen or a halo- ;i cn (Cl, Br), being black to blackish-blue pmvders, insoluble in water, alcohol, diluted alkalies and diluted acids, soluble in concentrated sulfuric acid with a blue color, dif fienltly soluble in hot nitrobenzene with a violet-brown to violet color, yielding on treatment with alkaline reducing agents,

such as hydrosillfite,

and cotton are dyed tints.

a vet from which wool dark-blue to blackish 3. As a new product, the ortho-ortho-diamino-para-para-dichlorothioindigo of the formula being a black to blackish-blue soluble in water, alco soluble in sulfuric aci steel-blue color, very 1Yowder, inhol and d' uted acids, d-monohydrate with a difiicultlyhsoluble in tures in presence of two witnesses.

ALBRECHT SCHMIDT. ERNST BRYK.

Witnesses:

J EAN GRUND, n CARL GRUND. 

